They threatened him with a hammer and stole cash. He died the following day due to heart and lung disease.

At the High Court in Edinburgh, Quinn was jailed for for six years and four months and Stevenson was told he must serve six years and nine months.

The court heard how Stevenson, who was wearing a balaclava, broke into the OAP's home while he was alone.

Gas mask

He demanded Mr McDermott's wallet before grabbing it and leaving.

Mr McDermott then alerted his neighbour William Henderson, who discovered £60 lying in the OAP's hallway.

A short time later, Stevenson returned, this time with Quinn, who was wearing a gas mask while clutching a hammer.

Quinn, who lived in the same block of flats as Mr McDermott, yelled at the pensioner to sit down or he was "getting it."

He then snatched the £60 found earlier and both accused raced out.

The court heard the robbery was a "very upsetting experience" for Mr McDermott.

Police arrived at his flat and found him to be agitated and having difficulty breathing - but the OAP insisted he did not want to go to hospital.

Stevenson and Quinn were arrested after they returned to the block of flats later that night.

Police also discovered two jackets, a hammer, a gas mask and a balaclava at a bridge nearby.

Pulmonary disease

The court heard how after the robbery, Mr McDermott's health deteriorated and he was taken to Crosshouse Hospital in Kilmarnock by his son and daughter.

He received treatment to help air-flow into his lungs, but did not improve and was pronounced dead in the early hours.

The cause of death was found to be heart and chronic pulmonary disease.

Quinn and Stevenson had faced an allegation of culpable homicide but prosecutors accepted their guilty plea to the reduced charge of assault and robbery after it was concluded there was no direct link between the attack and Mr McDermott's death.

It emerged in court that weeks before the robbery, Quinn stole £265 from his mother's purse.

Jailing both men, judge Lord Pentland said: "You have each pleaded guilty to participating in a violent attack on an elderly man in his own home.

"The complainer was a vulnerable person who suffered from a number of serious health difficulties.

"He was known to you both and it seems reasonable to infer that you regarded him as an easy target."